KR20070039598A - Method for producing cellulose derivatives containing amino groups, and uses of such derivatives in cosmetic preparations, water treatments and paper making - Google Patents

Abstract

The present invention relates to a method for producing an cellulose derivative containing an amino group by reacting an alkali cellulose or an alkali cellulose derivative with a reagent of the following formula.

X- (CH ₂ ) _n -NR ₁ R ₂

Where

X is a leaving group, preferably a chlorine, fluorine, iodine or sulfonic acid radical R'SO ₃ (R 'is an aromatic or aliphatic radical having 1 to 24 C atoms, such as para-toluyl or methyl),

n is necessarily 2 or more,

The radicals R ₁ and R ₂ independently of one another are aliphatic or branched or cyclic alkyl or aryl substituents having 1 to 24 C atoms and optionally substituted by heteroatoms, or H, or both radicals R ₁ and R ₂ are nitrogen and Together they can form a ring.

The invention is characterized in that water is used as the reaction medium and the ratio of cellulose to water is 1: 5 to 1:40 moles per anhydroglucose unit (AGU). The invention also relates to cellulose derivatives containing amino groups having a certain total degree of substitution, and to their use in cosmetic preparations, water treatment or paper manufacture.

 Cellulose, cellulose derivative, etherification, substitution degree

Description

METHOD FOR PRODUCING CELLULOSE DERIVATIVES WHICH CONTAIN AMINO GROUPS, AND THEIR USE IN COSMETIC PREPARATIONS, TREATING WATER TREATMENT AND IN THE MANUFACTURING OF PAPER}

The present invention relates to a process for preparing an cellulose derivative containing an amino group by reacting an alkali cellulose with an imino group containing reagent, wherein obtaining a water-soluble or water dispersible reaction product in one reaction step starting from an unsubstituted cellulose or a cellulose derivative. It is possible.

Chitosan (2-amino-2-deoxycellulose) has many possible uses only as cationic polysaccharides that are available in large amounts. Especially, it is used as an acid-stable thickener in cosmetic preparations, as a paper additive, and as a chelating agent and a flocculant. However, the separation of this natural polysaccharide was an expensive process, which was reflected in the high product price. High prices have limited the widespread use of chitosan.

Cellulose and its derivatives, mainly cellulose ethers containing hydroxyethyl groups, can be converted into cellulose derivatives containing amino groups, for example by reaction with aminoalkyl chlorides of the general formula Cl- (CH ₂ ) _n -NR ₂ . Sufficient mixing of the batch is required, which is ensured using a relatively large amount of organic solvent, for example as described in US-A 2 623 042. The degree of etherification obtained here is in most cases low and the amount of undesired by-products is large.

DE-A 1 946 722 suggests that this problem can be solved by using a kneader. In this case most of the already soluble cellulose derivatives are kneaded in a solvent / water mixture and reacted with N- (2-chloroethyl) -N, N-diethyl-ammonium chloride to give a degree of substitution of 0.3 to 1.0 per anhydroglucose unit. To achieve. However, a disadvantage of this is that when handling combustible and volatile organic solvents (mainly the peroxide-forming dioxanes of the cited patent) on an industrial scale, the cost must be increased to ensure safety.

Work-up and recovery of aqueous solvents and solvent mixtures require high investments, such as, for example, distillation columns, and, for example, increased treatment costs for distillation residues. Moreover, the use of combustible solvents increases the risk of fire and explosion.

It is an object of the present invention to provide an environmentally friendly, safe and cost effective production method for the preparation of cellulose derivatives containing amino groups.

Accordingly, the present invention provides a process for reacting an alkaline cellulose or an alkaline cellulose derivative with a reagent of the formula, characterized in that water is used as the reaction medium and the cellulose to water ratio is 1: 5 to 1:40 moles per anhydroglucose unit (AGU). A method for producing a cellulose derivative containing an amino group is provided.

X- (CH ₂ ) _n -NR ₁ R ₂

Where

X is a leaving group, preferably a chlorine, fluorine, iodine or sulfonic acid radical R'SO ³ (R 'is an aromatic or aliphatic radical having 1 to 24 C atoms, such as para-toluyl or methyl),

n is necessarily 2 or more,

The radicals R ₁ and R ₂ independently of one another are aliphatic or branched or cyclic alkyl or aryl substituents having 1 to 24 C atoms and optionally substituted by heteroatoms, or H, or both radicals R ₁ and R ₂ are nitrogen Together with the ring to form a ring.

According to the method according to the invention, it is possible to avoid the abovementioned disadvantages. It was surprisingly found that it is completely possible not to use organic solvents during the reaction. According to the invention, water is used as the reaction medium. Although an increase in the hydrolysis of the reagents is expected, the yields are surprisingly very good so that water soluble or at least water dispersible cellulose derivatives can be prepared in one step from cellulose. The organic solvent free process also greatly simplifies the work up of the batch. The resulting product does not contain residues of organic solvents used in the preparation, such as dioxane.

Cellulose with a wide variety of origins and property profiles can be used in the process of the invention, for example, cellulose (beech, spruce, pine, eucalyptus, cotton) mechanically subdivided in the form of debris, fibers or powders.

Cellulose derivatives may also be used, such as carboxymethyl, hydroxyethyl, hydroxypropyl, methyl and ethyl cellulose, and polysaccharides with mixed carboxymethyl, hydroxyethyl, hydroxypropyl, methyl and ethyl substituents. . Particular preference is given to methyl cellulose, hydroxyethyl cellulose, methyl hydroxyethyl cellulose, ethyl cellulose, ethyl hydroxyethyl cellulose, hydroxypropyl cellulose, methyl hydroxypropyl cellulose and ethyl hydroxypropyl cellulose.

Preference is given to using water insoluble cellulose ethers or cellulose ethers having a thermal flocculation point in water.

Preferably the total substitution degree of the cellulose derivative used for this reaction is 0.01-4, Especially preferably, it is 0.1-3. The average degree of substitution (DS _alkyl ) of the _alkyl substituent is 0 to 2.5, preferably 0 to 1.7. The molar substitution degree (MS _hydroxyalkyl ) of the _{hydroxyalkyl substituent} is 0 to 3.5, preferably 0 to 2.5.

Suitable etherifying agents are compounds of the formula

X- (CH ₂ ) _n -NR ₁ R ₂

Where

X is a leaving group, preferably a chlorine, bromine, iodine or sulfonic acid radical R'SO ³ (R 'is an aromatic or aliphatic radical having 1 to 24 C atoms, such as para-toluyl or methyl),

n is necessarily 2 or more,

The radicals R ₁ and R ₂ independently of one another are aliphatic or branched or cyclic alkyl or aryl substituents having 1 to 24 C atoms and optionally substituted by heteroatoms, or H. Both radicals R ₁ and R ₂ may form a ring with nitrogen.

X is particularly preferably chlorine.

Examples of etherification agents used according to the invention are N-2-chloroethyldiisopropylamine, N-2-chloroethyldiethylamine, N-3-chloropropyldiethyl-amine, N-2-chloroethyldimethyl Amines and N-2-chloropropyldimethylamine. The R ₁ and R ₂ radicals together with nitrogen may form a cyclic radical. Examples of etherification reagents of the invention wherein _two radicals R ₁ and R ₂ together with nitrogen form a ring are N-2-chloroethylpyrrolidine, N-2-chloroethylpiperidine and N-2- Chloroethyl morpholine. The etherification reagent can be used in the form of salts of ammonium, preferably hydrochloride. Either a solid or a solution of, for example, 65% or 50% by weight in water or another solvent can be used.

Preference is given to using N-2-chloroethyldiisopropylamine hydrochloride and N-2-chloroethyldiethylamine hydrochloride.

When cellulose is used as the starting material, about 0.1 to 3 moles, preferably about 0.3 to 2 moles, particularly preferably about 1 to 2 moles of etherification reagent per mole of anhydroglucose are used.

When a cellulose derivative is used, 0.01 to 1.5 mol, preferably 0.1 to 1 mol, and particularly preferably 0.1 to 0.8 mol of etherification reagent per mole of anhydrous glucose is sufficient.

Prior to the reaction, the cellulose or cellulose derivative is alkalized with about 5 to 60% by weight, preferably 30 to 55% by weight of aqueous base solution, preferably aqueous sodium hydroxide solution. Alkalization can be carried out directly in the reaction apparatus.

Also prior to the reaction, for example, cellulose or cellulose derivatives can be treated with a 5 to 60% by weight aqueous solution of a base, preferably sodium hydroxide, and stirred at room temperature for 10 to 120 minutes. It is then squeezed off to a constant residual moisture content. Cellulose activated in this way, such as cellulose optionally swollen with alkali cellulose or ammonium hydroxide, or activated cellulose derivative is then transferred to the reaction apparatus. Apart from cellulose, water insoluble cellulose derivatives are also suitable for this type of activation.

In principle, it is also possible to use, for example, tetraalkylammonium hydroxide or sodium carbonate as base, but preference is given to using alkali metal hydroxides, in particular sodium hydroxide. Part of the base can be added as a solid.

Preferably at least 0.1 equivalents, particularly preferably at least 0.3 equivalents of base are used per mole of etherification reagent. The amount of base used per mole of etherification reagent is 2 equivalents or less, preferably 1.5 mol or less, and in particularly preferred embodiments 1.2 mol or less.

If etherification reagents are used in the form of salts of ammonium, such as hydrochloride salts, the amount of base must therefore be increased. In such a case, it is further necessary to introduce at least an equimolar amount of base on the ammonium salt basis in order to release the amine from the salt of ammonium, such as hydrochloride.

The ratio of cellulose to water should be 1: 5 to 1:40 moles per mole of anhydroglucose units and preferably 1:10 to 1:30 parts by weight.

The reaction mixture is treated at a temperature of 15 to 95 ° C. for a period of 30 minutes to 12 hours, with 40 to 80 ° C. and 1 to 4 hours being the preferred parameters.

To avoid and minimize the decrease in molecular weight, the reaction is carried out in whole or in part under inert gases such as nitrogen or argon.

Suitable reaction mechanisms are known to those skilled in the art and can be determined by sizing experiments. The apparatus should allow for complete mixing or heating of the reactants.

Particularly suitable reaction mechanisms are kneaders, for example based on a separate kneader kneading chamber, in which two kneading blades, often of Z-shaped or sigma-shaped, optionally rotate while scraping each other and cover almost the whole of the kneading space. Due to the alternating blade surfaces moving closer together and further apart, high compression, tensile and shear forces act throughout the dough material. This also allows high viscosity materials to be mixed thoroughly. Ramesh R. Hemrajani in: Kirk-Othmer Encyclopedia of Chemical Technology, "Mixing and Blending; 12. Mixing of Dry Solids and Pastes"; John Wiley & Sons, 1995. DOI: 10.1002 / 0471238961.1309240908051318.a01, Article Online Posting Date: December 4, 2000.]

The reaction batch is placed in water or a solvent / water mixture, optionally neutralized, washed with a suitable solvent, dried and optionally comminuted.

Suitable solvents for washing the product are solvents in which the product swells little or not at all. In the process according to the invention, if neutralization is omitted, the cellulose derivative containing the amino group is preferably purified with water. If the filtrate is pH> 7, preferably pH> 8 (measured in 1 wt% aqueous solution), the product swells or only slightly dissolves. If necessary, further washing may then be carried out, optionally with an aqueous organic solvent or solvent mixture, such as acetone. The product can then be further treated in the form of the free amine or converted to the ammonium form completely or partly with an acid followed by further treatment.

If desired, the reaction batch may be treated after the reaction with an acid selected from the group comprising mineral or organic acids, preferably with hydrochloric acid. Further washing is preferably performed with an aqueous organic solvent or solvent mixture, such as aqueous acetone. If the product is neutralized in this way, its pH is preferably 7-4 and particularly preferably about 6.5-5.

If desired, the reaction product can be further reacted in the same type without special purification to increase the nitrogen content and thereby increase the DS. A further possibility according to the manner described in the process according to the invention is mixed etherification with different etherification reagents containing amino groups.

The process according to the invention is characterized by a simple procedure and gentle treatment of cellulose. This is universally applicable to many celluloses. Amino group containing cellulose derivatives having a degree of substitution of 0.5 to 1.5 can be obtained from unsubstituted cellulose in one reaction step. By not using an organic solvent, in most cases, use of an explosion-proof mechanism is unnecessary.

The present invention also provides

a) contains a substituent of the form-(CH ₂ ) _n -NR ₁ R ₂ attached to a cellulose or side chain, for example a hydroxyalkyl chain, wherein n is at least 2 and the R ₁ and R ₂ radicals are independent of each other An aliphatic or branched or cyclic alkyl or aryl substituent having 1 to 24 C atoms and optionally substituted with a heteroatom, or H, or two radicals R ₁ and R ₂ may form a ring together with nitrogen),

b) preferably-(CH ₂ ) _m -CH ₃ containing an alkyl substituent of the R ₃ type (m = 0 to 3 and DS _alkyl > 0.1),

c) preferably contains a hydroxyalkyl substituent selected from the group comprising hydroxyethyl, hydroxypropyl and hydroxybutyl (MS _hydroxyalkyl > 0.1),

e) [substituent-(CH ₂ ) _n -NR ₁ R ₂ Substituent— (CH ₂ ) _n —NR ₁ R ₂ , measured from the nitrogen content or after Zeisel cleavage [DS _alkyl for substituent R ₃ and hydroxyalkyl] , The total substitution degree (sum of the individual substitution degrees) of R ₃ and hydroxyalkyl is 0.8 to 2.5,

A cellulose derivative containing an amino group is provided.

The resulting cellulose derivatives containing amino groups can have a variety of uses, for example in cosmetic preparations, in particular hair protection products and shampoos. It may also be used as a flocculating aid, especially in water treatment, or as retention aids, especially in paper making.

Example  One

243 g (1.5 mol) of ground spruce sulfite pulp containing moisture in the atmosphere is alkalized in 5 l of 24% sodium hydroxide solution, squeeze at a ratio of 1: 4: 29 AGU: NaOH: water. -off) was transferred to a horizontal kneader of 5 l capacity. After heating to 65 ° C., 600 g (3 moles) of N, N-diisopropyl-aminoethyl chloride hydrochloride solution (65% solution) in 323 g of water are added with a strong dough and the dough further added for 3 hours. Continued. This resulted in a reactant ratio AGU: NaOH: agent: water in the solution of 1: 4: 2: 40. The reaction product formed was separated from the excess reaction solution by suction and washed with warm water until the pH of the outflowing wash water remained constant. The white powder obtained after drying had a nitrogen content of 5.80% (DS = 1.14).

Example  2

5 l of 25% sodium hydroxide solution was poured into 243 g (1.5 mol) of pulp and the mixture was stirred for 1 hour at room temperature. This was compressed until the anhydroglucose: NaOH: water ratio was 1: 4: 20. 491 g (3 mol) of N, N-diisopropyl-aminoethyl chloride (free base) was added to the formed alkaline cellulose over 5 minutes and the temperature was raised to 65 ° C. After 3 hours of reaction time, the high viscosity mass formed was filled with water and broken down by machine. Salts and byproducts were removed by intensive washing. The nitrogen content measured by elemental analysis was 5.85% (DS = 1.44).

Example  3

243 g (1.5 mol) of cellulose were alkalized in 5 l of 31% sodium hydroxide solution and the partially squeezed filter cake was pressed again until the anhydroglucose: NaOH: water ratio was 1: 4: 20. After heating to 55 ° C., 600 g (3 mol) of hydrochloride of N, N-diisopropylaminoethyl chloride were added to the solid form and the mixture was kneaded vigorously at 40 min ⁻¹ for 3 hours. The reaction product was washed with water. The nitrogen content measured after drying was 5.45% (DS = 1.26).

Example  4

595 ml of 17% sodium hydroxide solution was added to 169 g (1 mol) of N, N-dimethylaminoethyl cellulose (% N: 0.87-DS: 0.10) to give an AGU: NaOH: water ratio of 1: 3: 32.5. And then the mixture was kneaded thoroughly. After heating to 80 ° C. in the kneader, 327 g (2 mol) of N, N-diisopropylaminoethyl chloride were added. After kneading for 4 hours, the reaction mixture was treated with ethanol / water (1: 1 v / v) and neutralized with dilute hydrochloric acid. In this way the solubilized polymer was precipitated by addition of NaOH, rinsed with acetone and dried. The measured nitrogen content was 6.03% (DS = 1.22).

Example  5

327 g (2 mol) of N, N-diisopropylaminoethyl chloride were added to 162 g (1 mol) of wood pulp and the mixture was stored at room temperature for 12 hours with no air. 300 ml of 30% sodium hydroxide solution was then added and the batch kneaded at 60 ° C. for 4 hours. As a result, the reactant ratio in the solution was anhydroglucose: NaOH: agent: water = 1: 3: 2: 15.5. At the end of the reaction, the product was compressed and washed repeatedly with water until the outflowing wash water was nearly neutral. After drying, the white product granulated. The nitrogen content found by elemental analysis was 5.97% (DS = 1.50).

Example  6

50% sodium hydroxide solution (6 mol) was added to the milled pulp containing 243 g (1.5 mol) of atmospheric moisture in the mixer and the components were mixed for 45 minutes. 3 mol of N, N-diisopropylaminoethyl chloride (65% solution) was added and the reaction continued for an additional 4 hours. As a result, the reactant ratio AGU: NaOH: agent: water in the reaction mixture was 1: 4: 2: 21.5. The reaction product formed was aspirated, separated from excess reaction liquid, and washed with warm water until the pH of the outflowing wash water was kept constant. The white powder obtained after drying had a nitrogen content of 5.80% (DS = 1.14).

Claims (10)

Cellulose containing an amino group by reacting an alkali cellulose or an alkali cellulose derivative with a reagent of the formula: characterized in that water is used as the reaction medium and the ratio of cellulose to water is 1: 5 to 1:40 mol per anhydroglucose unit (AGU). Method of Making Derivatives. X- (CH ₂ ) _n -NR ₁ R ₂ Where X is a leaving group, preferably a chlorine, fluorine, iodine or sulfonic acid radical R'SO ₃ (R 'is an aromatic or aliphatic radical having 1 to 24 C atoms, such as para-toluyl or methyl), n is necessarily 2 or more, The radicals R ₁ and R ₂ independently of one another are aliphatic or branched or cyclic alkyl or aryl substituents having 1 to 24 C atoms and optionally substituted by heteroatoms, or H, or both radicals R ₁ and R ₂ are nitrogen and Together they can form a ring. The method of claim 1, wherein from 0.1 to 3 moles of etherification reagent per AGU is used. The method of claim 1 wherein cellulose ether is used as the cellulose derivative. 4. The method of claim 3 wherein the average degree of substitution (DS _alkyl ) of the _alkyl substituents is from 0 to 2.5 and particularly preferably from 0 to 1.7, and the molar substitution degree (MS _hydroxyalkyl ) of the _{hydroxyalkyl substituents} is from 0 to 3.5 and in particular A cellulose ether, preferably 0 to 2.5, with a total substitution of 0.01 to 4 and preferably 0.1 to 3, is used as the cellulose derivative. The method of claim 1, wherein 0.01 to 1.5 moles of etherification reagent are used per anhydroglucose unit. The method of claim 1 wherein the ratio of cellulose to water is 1:10 to 1:30 moles per mole of anhydroglucose units. a) a substituent of the form-(CH ₂ ) _n -NR ₁ R ₂ , wherein n is at least 2 and the R ₁ and R ₂ radicals independently of one another have 1 to 24 C atoms and are optionally substituted with heteroatoms Aliphatic or branched or cyclic alkyl or aryl substituents, or H, or both radicals R ₁ and R ₂ may form a ring with nitrogen), b) preferably-(CH ₂ ) _m -CH ₃ containing alkyl substituents of the R ₃ type (m = 0 to 3 and DS> 0.1), c) [substituent-(CH ₂ ) _n -NR ₁ R ₂ Substituent— (CH ₂ ) _n —NR ₁ R ₂ , measured from nitrogen content or measured after Zeisel cleavage [to substituent R ₃ ] And the total substitution degree (sum of the individual substitution degrees) of R ₃ is 0.8 to 2 per anhydroglucose unit, A cellulose derivative containing an amino group. a) contains a substituent of the form-(CH ₂ ) _n -NR ₁ R ₂ attached to a cellulose or side chain, for example a hydroxyalkyl chain, wherein n is at least 2 and the R ₁ and R ₂ radicals are independent of each other An aliphatic or branched or cyclic alkyl or aryl substituent having 1 to 24 C atoms and optionally substituted with a heteroatom, or H, or both radicals R ₁ and R ₂ may form a ring together with nitrogen), b) preferably-(CH ₂ ) _m -CH ₃ containing an alkyl substituent of the R ₃ type (m = 0 to 3 and DS _alkyl > 0.1), c) preferably -CH ₂ -CH (C _p H _{2p +1} ) O- {CH ₂ -CH (C _p H _{2p -1} ) O} _q -C _r H _{2r +1} where p = 0 or 1 , a hydroxyalkyl substituent of type R ₄ wherein q = 0 to 30, r = 0 or 1 and MS _hydroxyalkyl > 0.1), d) [substituent-(CH ₂ ) _n -NR ₁ R ₂ Substituent-(CH ₂ ) _n -NR ₁ R ₂ , measured from nitrogen content or measured after Zeisel cleavage [for substituents R ₃ and R ₄ ] , The total substitution degree (sum of individual substitution degree) of R ₃ and R ₄ is 0.8 to 2.5 per anhydroglucose unit, A cellulose derivative containing an amino group. Use in cosmetic preparations of cellulose derivatives containing amino groups obtainable according to claim 1. Use of the cellulose derivative containing an amino group obtainable according to claim 1 in water treatment or paper manufacture.